Semiconductor chips such as, for example, light-emitting diodes (LEDs) age more rapidly under the influence of moisture than in a dry atmosphere. This ageing process is based, inter alia, on corrosion effects and leakage currents in or at the semiconductor chip. This ageing process is particularly pronounced when the LEDs are not operated, since the latter are then at a lower temperature than in the operating state, as a result of which a film of liquid can form, for example, directly on the semiconductor chip on account of condensation of moisture stored in the air. A liquid film of this type disadvantageously fosters and accelerates the degradation of the semiconductor chip.
Furthermore, the wavelength of the radiation emitted by the semiconductor chip disadvantageously shifts with a change of temperature in the semiconductor chip. By way of example, such a wavelength shift based on temperature changes can occur upon switch-on and start-up of the semiconductor chip or during pulsed operation of the semiconductor chip.
In order to reduce the above mentioned disadvantages of the ageing effects and wavelength shifts, it is conventionally known, for example, to form a protective housing or a protective coating on the semiconductor chip, which keep the moisture away from the semiconductor chip and thus make the semiconductor chip more stable against corrosion at the expense of the luminous efficiency and radiation efficiency.